ZDI-11-027: Novell GroupWise Internet Agent TZID Parsing Remote Code Execution Vulnerability

http://www.zerodayinitiative.com/advisories/ZDI-11-027

January 26, 2011

-- CVE ID:
CVE-2010-4325

-- CVSS:
10, (AV:N/AC:L/Au:N/C:C/I:C/A:C)

-- Affected Vendors:
Novell

-- Affected Products:
Novell Groupwise

-- TippingPoint(TM) IPS Customer Protection:
TippingPoint IPS customers have been protected against this
vulnerability by Digital Vaccine protection filter ID 10797.
For further product information on the TippingPoint IPS, visit:

   http://www.tippingpoint.com

-- Vulnerability Details:
This vulnerability allows remote attackers to execute arbitrary code on
vulnerable installations of Novell GroupWise. Authentication is not
required to exploit this vulnerability.

The specific flaw exists within the gwwww1.dll module responsible for
parsing VCALENDAR data within e-mail messages. When the code encounters
a TZID variable it allocates up to 0xFFFF bytes for the variable's
value. It then proceeds to copy the value into the fixed-length buffer
without checking if it will fit. By specifying a large enough string in
the e-mail, an attacker can overflow the buffer and execute arbitrary
code under the context of the SYSTEM user.

-- Vendor Response:
Novell has issued an update to correct this vulnerability. More
details can be found at:

http://www.novell.com/support/search.do?cmd=displayKC&docType=kc&externalId=7007638&sliceId=1&docTypeID=DT_TID_1_1&dialogID=199990255&stateId=0%200%20199988170


-- Disclosure Timeline:
2010-11-30 - Vulnerability reported to vendor
2011-01-26 - Coordinated public release of advisory

-- Credit:
This vulnerability was discovered by:
    * Anonymous

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